Why the amount allowable provincial tuition transfer from my son did not let me to entry max amount on my return? my son want to transfer all max amount to me

my son wants to transfer all allowable provincial tuition to me say $3000. but when I enter into my tax return, the  turbo tax the max is $2500. Is there a bug?  I still have room to reduct my tax.  Shall I only claim $2500.  the left over $500 for my son to carry forward?